channels and ohms?

[CanuckCRX]

ok, heres the deal,
i would say i know the jist and a lil more about the whole car audio section. but theres one thing i STILL cant figure out. I tried to get a buddy of mine to explain it, but i still cant grasp the concept of running amps to subs. How many channels do you need? one channel for 2 subs? 1 channel for each sub?
im getting a rockford 200s amp with the following specs:
200 RMSx1 at 4 ohms
100 RMSx2 at 2 ohms
50 RMSx2 at 4 ohms
400 peak

with 2 - 10" type S subs, which demand a 4 ohm input, i think they're something like 600 peak with 200 RMS
now....do i just put the 2 channel together to make 1 channel at 4 ohms to go to 2 subs? or do i need 1 channel to each at 4 ohms, which ill only get 50 RMS

[PaulD]

most people bridge an amp like that to one channel and put the subs in parallel - the reason is because (all else being equal) bridging the amp to the same load often double it's power output and putting the speakers in parallel also can double the amps power output. As an example:

50W X 2 with 2 4ohm speakers = 100W total
100W X 2 with 2 2ohm speakers = 200W total
200W X 1 with the amp bridged and 1 - 4ohm speaker = 200W total
400W X 1 with the amp bridged and 2 - 4ohms speakers connected in parallel = 400W

(most amps cannot handle the last scenario)

[Cfmotorsports]

with that amp and the speekers you are getting you will only be able to get 50 watts out of the amp.

the amp is 2ohm stereo stable and 4 ohm mono stable if you bridge you 2 4ohm speekers down you will have a 2 ohn mono load and the amp will shut down. you could wire the speekers to get an8ohm load but there would be no real benefit to that. but you could run 4 4ohm subs to that amp and bridge it down to 2ohm stereo, but that would still probly not be unuff power to drive them hard.

[CanuckCRX]

hmm....are you positive.....anyone on here to back that up...im not gonna be a bitch, and judge your knowledge, thats what this thing is for, to get some help and opinions but....buddy of mine has a friend that works at the local shop, and he said the 2 type S would be perfect for the 200s, i mean a guy i know has 2 rockford punch 10 inchers running off a 600w peak amp, and it POUNDS, and a while back another dude i know had 2 12's running off a 400w peak amp im POSITIVE and it shook the car like a mutha****er, the only other option i gave was getting the 300s instead:


300 RMSx1 at 4 ohms
150 RMSx2 at 2 ohms
75 RMSx2 at 4 ohms
600 peak

[strodda]

yea cf is right.

your amp is only 4ohm stable when bridged. if you parallel a pair of 4ohm subs, that creates a 2ohm load. your only option is to put a sub to each channel. what would be better is either getting a more powerful amp, or 8ohm subs.

[BigBearWest]

what do u mean by setting the subs up in parrel(sp?)?

[strodda]

parallel is when you have the + and - from both speakers going to the same terminal. if you had 8ohm subs, you could wire the speakers positives and negatives together, creating a 4ohm load. then you would bridge the amp. then you would get the full 200w to the pair.

your only option with that amp and speaker set up is to wire each speaker to its own terminal, meaning you'd only get 50w/ch. i'd say dump one speaker, bridge the amp, and have 200w to one sub.

[Cfmotorsports]

have you pruchased the subs yet, if not and you are sure you want 2 subs, (i only run 1 JLw6 d3 and I compete on this setup and win) then bye either 2 8ohm subs or get a set of DVC (duel voice coil) subs. or get a secong amp to run the other sub.

[CanuckCRX]

nope, havent purchased yet, still in the deciding stage what i want, maybe ill just get one 12" or something
so, if i only got 4 ohm speakers, if i run in parallel i get low power, but if i run 8 ohm speakers in parallel, i get all the power i need, thats confusing, but alright. Ill take a look at some 8 ohms pricewise in the next few days, any recomendations for 8 ohms out there?

[strodda]

well i dont know of any stable bridged 2ohm amps, but the amp you were talking about is not. therefore you cant parallel a pair of 4ohm subs onto a bridged amp. and the only 8ohm sub i know offhand is the jbl gt. i'd say get the amp you wanted, and buy one 12". more power to the sub and saves alot of space.

[PaulD]

there are plenty of amps that are stable into 2 ohms bridged - but that is a hard load to drive

[Cfmotorsports]

should be able to get the subs you are looking at in a 8ohm they mite have to order them but the can be got if you are stuck on fosgate than go with 500.1 its 2 ohm mono stable and will run it all day long.

[CanuckCRX]

any idea how much the price will go up if i need them to get some 8 ohm's for me,
anywho, the 500.1, is that a power amp or a punch amp
whats the specs?
so if i bridge it up, ill get? and this will be good quality bang for the buck

sorry with all the ?'s

[strodda]

well first pick an amp or sub. if you want to get a mono amp cf mentioned, that'd work great. since it is 2ohm stable, just go ahead and get those type-s you wanted. what would you prefer, more power to one sub, or less to two?

[Cfmotorsports]

not sure the specs on the 500.1 but the fosgate web site should be able to tell you that and yes it is a power punch 500.1 the amp is a bit more money i think my shop sells them for about 350 or so but with that you could run the 4omn speekers that you wanted from the start.


the price between the 8ohm and 4 ohm should be the same or very close the 8hm is somtimes cheeper.




QUOTE]Originally posted by CanuckCRX
any idea how much the price will go up if i need them to get some 8 ohm's for me,
anywho, the 500.1, is that a power amp or a punch amp
whats the specs?
so if i bridge it up, ill get? and this will be good quality bang for the buck

sorry with all the ?'s [/quote]